Beverages are sold in glass and plastic containers having an interior void space which is pressurized (if carbonated) or evacuated (if fermented) and then sealed by an original factory closure such as a screw cap or cork. The purpose of the closure is to seal the container and maintain the void space under pressure or evacuated until the container is opened for dispensing the beverage. Some beverage containers are relatively small, in the six- to ten-ounce range, and are sealed by a disposable cap which is discarded after the beverage container is opened. Larger beverage containers, for example in the two- to three-liter range, are provided with a reusable screw cap closure for resealing the container after a portion of the beverage has been served.
Carbonated beverages typically contain dissolved carbon dioxide gas which will escape into the atmosphere unless the container is pressurized and sealed. The flavor of such carbonated beverages turns flat in the absence of the dissolved carbon dioxide gas. The loss of carbonation can be reduced somewhat by sealing the beverage container after use. However, because of the relatively large volume of some beverage containers, the carbonization will be released into the unpressurized open space within the container, with the result that the flavor of the remaining beverage is impaired. Accordingly, the quality of the beverage in such larger containers will gradually deteriorate, with the result that a substantial portion of the beverage will become unpalatable, and will be discarded.
The quality and taste of other beverages, for example wine, is affected by exposure to and reaction with oxygen contained within the air. For this reason, the quality and flavor of beverages such as wine which react with oxygen will gradually deteriorate after the wine bottle has been uncorked. For that reason, it is customary to discard any wine which may be left over and not consumed within a few hours after the wine bottle is uncorked.